The present invention relates to a document folding apparatus and a method for folding documents.
Printed documents usually need to be folded to fit in an envelope of a convenient size. Documents may typically comprise printed A4 sheets of paper, since this is the size with which modern printers work most efficiently, but may alternatively comprise a typical correspondence size, eg USA letter size.
Typically document sheets are folded once, in a so-called V-fold, or twice in a so-called Z-fold (which sandwiches the middle third of the sheet between the outer two thirds), or a C-fold (in which one of the outer thirds is sandwiched between the other outer third and the middle third). Traditionally this is done using a standard buckle fold apparatus, as shown in FIG. 1. The document to be folded is fed by rollers into a dead-end fold box. The leading edge of the document encounters the end of the box but the trailing edge continues to be driven forward. Consequently the document buckles about a line between the leading and the trailing edge determined by the depth of the box in relation to the length of the document, and the buckling portion is caught in the nip of subsequent rollers to complete the fold and flatten the fold line.
However such known apparatus cannot easily accept documents to which rigid material is attached, for example credit cards or compact discs because they cannot easily negotiate the tight turns inherent in the dead end box folder. Such rigid material is increasingly distributed by mail. For example credit and debit cards are sent attached to forms printed with information identifying the intended recipient and ideally the forms are printed on A4 or letter size paper for printer efficiency and must therefore be folded. Such forms are currently folded using complex expensive equipment which tends to operate at a relatively slow speed and cannot easily be adapted to different fold configurations.
There is a need for a more versatile, speedier and less expensive document folding apparatus.